Automatic air valve



June 15 1926.

H. K. KRIEBEL AUTOMATIC AIR VALVE Filed August 22, 1922 q I a F FIG-3,

A TTORNEY.

Patented June 15, 19263.

unirs' stares HOSEA K. KRIEBEL, OF PHILADELPHIA, EENNSYLVANIA.

AUTOMATIC AIR VALVE.

Application filed August 22, 1922.

The object of my invention is to provide an effective and positivelyacting thermostatic air valve for automatically operating as an airventing device for radiators of a steam heating system; and which hasalso capacity of acting as a check valve to pre vent inflow of air inthe event of a partial vacuum being created within the radiator by thecondensation of the steam therein.

With the above and other objects in view, the nature of which will bemore fully understood from the description hereinafter, the inventiionconsists in the novel construction of automatic air valves, ashereinafter more fully described and defined in the claims.

Referring to the drawings: Fig. 1 is a side view, with part in section,illustrating my improved automatic air valve; Fig. 2 is an elevation ofthe upper portion of the same with the hood in section; and Fig. 3 is avertical section of the character of Fig. 1, but illustrating a modifiedconstruction.

2 is the main casing and is provided with a screw threaded nipple 8 forattachment to the radiator. Arranged within this casing is athermostatic bellows 9 of any suitable construction, containing avolatile fluid or condensable gas, which under the application of steamheat expands to expand the bellows and upon cooling, as when no steam ispassing, permits the bellows to contract. Thermostatically Operatingbellows of this charactor for use in air valves have been heretofore inuse and this device of itself is not of my invention.

The upper part of the casing 2 is provided with a hub 41; having aninternal or external screw threaded aperture in which is screwed a plug5 having a valve seat 6 and a tubular passage 7 leading thereto from theinterlor of the casing 2. The upper end of the thermostaticallyoperating bellows 9 is fitted with a valve piece 8 which is looselyguided in the tubular passage 7 and is made conical on the top to seatupon the valve seat 6 and thus control the venting orifice from theeasing 2 in such manner that when air is passing from the radiator, thebellows 9 holds the valve piece 8 away from its seat 6 and permits theair to escape under the pressure of the steam which drives the air fromthe radiator. hen, however, steam, following the air, attempts to passthrough thecasing 2, the bellows 9 is expanded and in doing so causesthe valve piece 8 to seat and shut Serial No. 583,489.

oil the escape of the steam. If, however, the radiator be shut off fromthe steam supply. the steam within it will condense and produce apartial Vacuum within the same and if not otherwise prevented, wouldcause air to be sucked through the valve into the casing and thence intothe radiator. Similarly, during the operation of the radiator, it some--times happens that, in case of a severe drop in atmospheric temperatureor from a shortage of steam supply, condensation in the radiator takesplace to such an extent that a partial vacuum is created and air drawninto the radiator. To prevent this inflow of air, I provide the airvalve with a check valve means of specific character which effectivelyprevents such inflow and this I will now describe.

The plug 5 is provided with a collar or shoulder portion which clampsdown upon the top or" the hub 1 to make a steam and air tight joint andits upper portion is extended upward in a body 10 having a tubular airpassage 11, the bottom thereof opening through the valve seat 6 and itstop opening laterally through a vertically arranged valve seat 17. Acheck valve 12 rests by gravity against the valve seat, so as to act asa check valve to prevent air entering the passage 11 but offering nomaterial obstruction to the escape of air from the passage when ventingthe radiator. As shown in Figs. 1 and 2, this check Valve 12 is hung bylinks 13 from a pivot 14: in an angular projection at the top of thebody 10; and it will be noted that the pivot 14 is slightly to one sideof the center of gravity of the valve 12 so that it tends to seat by theaction of gravity and hence is very sensitive to pressures in bothdirections. This air check valve construction is very small and beingdelicate is protected by a hood 15 in dome form which may either bescrewed upon the outside of the hub 1, as shown, or may be made as a tihtly fitting sleeve joint. This hood not only protects the check valvestructure against injury from breakage, but keeps out dirt and dust. 16is a side aperture or vent through the wall of the hood to permit theescape of air when venting the radiator.

In place of having the valve 12 in the manner shown in Fig. 1, it may bemade as shown in Fig. 3, in which the valve piece 12 may be looselycarried on the end of an arm 13 which extends upwardly and inwardly to apivot connection i l on the lateral projecting portion of the body 10.In this case, as in that of Figs. 1 and 3, the valve piece seats bygravity.

It will now be apparent that I have de vised a novel and usefulconstruction which embodies the features of advantage enun'ierated asdesirable, and while I have in the present instance shown and describedthe preferred embodiment thereof which has been found in practice togive satisfactory and reliable results, it is to be understood that l donot restrict myself to the details, as the same are susceptible or"modification in various particulars 'WltllOUlL departing from the spiritor scope of the invention.

Having now described my invention, what I claim as new and desire tosecure by Letters Patent is:

1. An automatic air valve, comprising a casing and a thermostaticexpansive ele ment therein having a valve piece oirected upwardly, incombination with a plug in one piece screwed into the upper part of thecasing and having an angular tubular passage terminating at the bottomwith an air vent seat directed toward and in alinement with the valvepiece of the thermostatic element and at its upper part provided with alaterally opening check valve seat whose plane is substantiallyvertical, and a gravity actuated check valve freely suspended from theplug like a pendulum in a substantially ver ical position and normallyseating upon the outside of the check valve seat with a very lightcontact so as to oller practically no resistance to opening in responseto very small pressure released by the thermostatic valve.

2. The invention according to claim 1. wherein further, the plug extendsupwardly from the casing and has its check valve seat at a distanceabove the vent valve seat, and in which the check valve is hung at theoutside of the plug extension and freely e1;- posed from all sides, anda hood independent the check valve and its seat is detacliably securedto the casing and extending over the plug to enclose it and the checkvalve, said hood having a vent aperture and when rem-red exposing all ofthe working parts of the check va ve and its sup iiorling means wherebythey may be directly handled in case of derangement.

In testimony of which invention I here unto set my hand.

